Electronic monitoring device for power press brakes and similar devices
First Claim
1. An electronic monitoring device for indicating when the stopping time of a brake adapted to stop the motion of a mechanical drive system upon receipt of a stop signal exceeds a preselected time, said drive system having a shaft rotating at a velocity corresponding to said motion of said drive system, means for creating a stop signal and means for applying said brake in response to said stop signal, said monitoring device comprising:
- a digital counter having an input for counting pulses;
means for starting a counting interval of said counter in response to said stop signal;
means for terminating said counting interval when said shaft is stopped;
means for applying counting pulses to said counter input;
means for creating a first signal when said digital counter has counted to a selected number indicative of proper brake action;
means creating a second signal when said shaft has stopped;
indicating means actuated upon creation of said first signal before said second signal;
means for creating a checking counting interval for said counter prior to said stop signal, means for creating a generally fixed time base train of counting pulses, said frequency being sufficient to count to said selected number during said checking counting interval, and means responsive to lack of creation of said first signal during said checking counting interval for creating a drive system shut down signal.
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0 Petitions
Accused Products
Abstract
There is provided an electronic monitoring device for indicating when the stopping time or stopping distance of a brake adapted to stop the motion of the power press drive system exceeds a preselected time or distance. In accordance with one aspect of this device, there is provided means for creating a selected number of control pulses having a time spacing between successive control pulses inversely proportional to the rotational velocity of the press shaft, a digital counter having an input for counting pulses and means for starting the counter upon creation of a stop signal for the press, means for creating counting pulses having a known time base frequency, means for directing the counting pulse to the input of the digital counter, means for creating a first signal when the digital counter has counted to a selected number, means for creating a second signal when the time spacing of successive control pulses exceeds a preselected time and indicating means actuated upon creation of the first signal before creation of the second signal.
15 Citations
30 Claims
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1. An electronic monitoring device for indicating when the stopping time of a brake adapted to stop the motion of a mechanical drive system upon receipt of a stop signal exceeds a preselected time, said drive system having a shaft rotating at a velocity corresponding to said motion of said drive system, means for creating a stop signal and means for applying said brake in response to said stop signal, said monitoring device comprising:
- a digital counter having an input for counting pulses;
means for starting a counting interval of said counter in response to said stop signal;
means for terminating said counting interval when said shaft is stopped;
means for applying counting pulses to said counter input;
means for creating a first signal when said digital counter has counted to a selected number indicative of proper brake action;
means creating a second signal when said shaft has stopped;
indicating means actuated upon creation of said first signal before said second signal;
means for creating a checking counting interval for said counter prior to said stop signal, means for creating a generally fixed time base train of counting pulses, said frequency being sufficient to count to said selected number during said checking counting interval, and means responsive to lack of creation of said first signal during said checking counting interval for creating a drive system shut down signal.
- a digital counter having an input for counting pulses;
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2. An electronic monitoring device for indicating when the stopping time of a brake adapted to stop the motion of a mechanical drive system upon receipt of a stop signal exceeds a preselected time, said drive system having a shaft rotating at a velocity corresponding to said motion of said drive system, means for creating a stop signal and means for applying said brake in response to said stop signal, said monitoring device comprising:
- means for creating a control pulse upon rotation of said shaft through each of successive angular sectors;
a digital counter having an input means for receiving counting pulses and means for enabling said counter upon creation of an enabling signal;
logic means for creating said enabling signal upon creation of a stop signal;
means for stopping counting of said counter upon stopping of said shaft;
means for directing said control pulses to said counter at least while said counter is counting;
means responsive to said counter counting to a selected number representative of a shaft angular displacement after said stop signal for creating a fault signal and means for manually changing said selected number. - View Dependent Claims (3)
- means for creating a control pulse upon rotation of said shaft through each of successive angular sectors;
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4. An electronic monitoring device for indicating when the stopping time of a brake adapted to stop the motion of a mechanical drive system upon receipt of a stop signal exceeds a preselected time, said drive system having a shaft rotating at a velocity corresponding to said motion of said drive system, means for creating a stop signal and means for applying said brake in response to said stop signal, said monitoring device comprising:
- means for creating control pulses having a time spacing between successive control pulses inversely proportional to the rotational velocity of said shaft;
a digital counter having an input for counting pulses and means for starting said counter upon creation of said stop signal;
means for creating counting pulses having a known time base frequency;
means for directing said counting pulses to the input of said digital counter;
means for creating a first signal when said digital counter has counted to a selected number;
means for creating a second signal when said time spacing of successive control pulses exceeds a selected time; and
indicating means actuated upon creation of said first signal before creation of said second signal. - View Dependent Claims (5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
- means for creating control pulses having a time spacing between successive control pulses inversely proportional to the rotational velocity of said shaft;
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20. An electronic monitoring device for indicating when the stopping time of a brake adapted to stop the motion of a mechanical drive system upon receipt of a stop signal exceeds a preselected time, said system having means for creating a stop signal and applying said brake, said monitoring device comprising:
- a digital counter having an input for counting pulses and means for creating an output signal when said counter counts a selected number of pulses;
first means responsive to said stop signal for applying a first train of pulses to said counter input, said first train of pulses having an effective time base frequency;
second means for applying a second train of pulses to said counter input for a time period prior to said stop signal; and
an oscillator for creating said second train of pulses with a second time base frequency substantially higher than the effective frequency of said first train of pulses, said second time base frequency being sufficient for said counter to reach said selected number during said time period. - View Dependent Claims (21)
- a digital counter having an input for counting pulses and means for creating an output signal when said counter counts a selected number of pulses;
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22. An electronic monitoring device for indicating when the stopping time of a brake adapted to stop the motion of a mechanical drive system upon receipt of a stop signal exceeds a preselected time, said drive system having a shaft rotating at a velocity corresponding to said motion of said drive system, means for creating a stop signal and means for applying said brake in response to said stop signal, said monitoring device comprising:
- a digital counter having an input for counting pulses;
means for starting a counting interval of said counter in response to said stop signal;
means for terminating said counting interval when said shaft is stopped;
means for applying counting pulses to said counter input;
means for creating a first signal when said digital counter has counted to a selected number indicative of proper brake action;
means creating a second signal when said shaft has stopped;
indicating means actuated upon creation of said first signal before said second signal; and
means for delaying said count interval starting means for a given time period after said stop signal. - View Dependent Claims (23, 24)
- a digital counter having an input for counting pulses;
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25. An electronic monitoring device for a drive system having a braking system adapted to stop the said drive system, said monitoring device being used for indicating when said braking system fails to stop said drive system within an allowable tolerance, said drive system including means for initiating operation of said braking system in response to a stop signal, said monitoring device including:
- means for generating pulses having a selected number which, if exceeded, is indicative of said stopping by said braking system being beyond said allowable tolerance;
digital means for receiving said pulses and for counting said pulses toward said selected number in a counting interval;
means for starting said counting interval in response to said stop signal;
means for terminating said counting interval when said driven member is stopped;
means for generating a signal in response to counting to said selected number during said counting interval; and
indicator means responsive to generation of said signal for indicating when said braking system is stopping said drive system outside said allowable tolerance; and
means for delaying said counting interval starting means for a given time period after said stop signal. - View Dependent Claims (26, 27)
- means for generating pulses having a selected number which, if exceeded, is indicative of said stopping by said braking system being beyond said allowable tolerance;
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28. An electronic monitoring device for a drive system having a braking system adapted to stop said drive system, said monitoring device being used for indicating when said braking system fails to stop said drive system within an allowable tolerance, said drive system including means for initiating operation of said braking system in response to a stop signal, to stop said drive system in a braking interval determined by the stopping characteristics of said braking system, said monitoring device comprising:
- means for generating pulses having a known relationship to said allowable tolerance;
means for creating a counting interval corresponding to said braking interval;
digital means for counting said pulses during a counting interval, said digital means includes means for creating a fault signal when said counting means counts to a given number indicative of operation of said braking system outside said allowable tolerance;
means for displaying said given number;
means for changing said given number;
means for indicating the creation of said fault signal; and
said pulse generating means being a device for creating a pulse when said drive system is moved a selected angular distance. - View Dependent Claims (29)
- means for generating pulses having a known relationship to said allowable tolerance;
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30. An electronic monitoring device for a drive system having a braking system adapted to stop said drive system, said monitoring device being used for indicating when said braking system fails to stop said drive system within an allowable tolerance, said drive system including means for initiating operation of said braking system in response to a stop signal, to stop said drive system in a braking interval determined by the stopping characteristics of said braking system, said monitoring device comprising:
- means for generating pulses having a known relationship to said allowable tolerance;
means for creating a counting interval corresponding to said braking interval;
digital means for counting said pulses during a counting interval, said digital means includes means for creating a fault signal when said counting means counts to a given number indicative of operation of said braking system outside said allowable tolerance;
means for displaying said given number;
means for changing said given number;
means for indicating the creation of said fault signal; and
said pulse generating means being an oscillator means for producing pulses at a generally fixed time based rate.
- means for generating pulses having a known relationship to said allowable tolerance;
Specification